diff --git a/runtime/imp/build.sh b/runtime/imp/build.sh
index 933cd77aa..43d73660c 100755
--- a/runtime/imp/build.sh
+++ b/runtime/imp/build.sh
@@ -1,18 +1,25 @@
 #!/bin/bash
 
-BUILD_COMM="/home/patrick/maven3/bin/mvn"
+# On CS machines, load the module 'java/maven'
+# On personal machines, make sure 'mvn' is in your path.
+BUILD_COMM="mvn"
+
+if [ ! -d ../../jars ]; then
+  echo "In wrong directory?  Run from silver/runtime/imp as ./build.sh"
+  exit 1
+fi
+
 CURR_DIR=`pwd`
 
 cd edu.umn.cs.melt.copper
 $BUILD_COMM clean install
-cd $CURR_DIR
+cd ..
 
 cd edu.umn.cs.melt.silver  
 $BUILD_COMM clean install
-cd $CURR_DIR
+cd ..
 
 cd main
 $BUILD_COMM clean package
-cp target/edu.umn.cs.melt.ide.copper-*.jar $CURR_DIR
+cp target/edu.umn.cs.melt.ide.copper-*.jar ../../../jars
 
-cd $CURR_DIR